Dec 30, Perth: Another group of Sri Lankan asylum seekers have opted to return home, the Department of Immigration and Citizenship of Australia said today.

The 33 Sri Lankan men have chosen to return home from both the Nauru Regional Processing Centre and the Australian mainland.

According to a departmental spokesman 12 men detained at Nauru joined 21 others who were detained in Western Australia and boarded a charter flight from Perth to Colombo Sunday morning.

An additional four Sri Lankan men have returned earlier this week.

The spokesman said the men departed voluntarily.

"They chose not to pursue their asylum claims and no longer seek to engage Australia’s protection obligations. This is further proof that there is no advantage engaging with people smugglers," he said.

The spokesman said that further transfers to Nauru would occur in coming weeks and the department expected more people would choose to return home.

Since implementing new immigration policies from August 13 to process new illegal arrivals at regional processing centers in Nauru and Manus Island in Papua New Guinea, Australia has returned 883 asylum seekers both voluntarily and involuntarily.

The asylum seekers are required to stay in the offshore detention centers for a long time before they can get a visa.

People in a regional processing center or immigration detention can voluntarily return to their home country at any time. People who return voluntarily have access to reintegration assistance depending on their status.

The Australian government says it will continue to return people where they do not engage Australia's international obligations.